Dynamic bone fracture plates

ABSTRACT

A bone fracture plate assembly including female and male plate portions. The female plate portion has a post, a female dovetail, and an extending arm with a group of ratchet teeth. The male plate portion has two upstanding posts, a male dovetail for coupling to the female dovetail so that the plate portions move linearly with respect to each other, a slot for the arm, and a pawl for engaging the ratchet teeth. A spring, coupled to the posts of the plate portions, dynamically connects the plate portions by applying a compressive load therebetween. The spring has a pair of elongated ears, each defining a slot to allow for relative movement of the plate portions. The ratchet teeth are engaged by the pawl to retain the plate portions together, and the spring mounts on the posts of the plate portions such that the spring biases the plate portions together.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.13/891,839 filed May 10, 2013, which is a continuation-in-part of U.S.patent application Ser. No. 13/586,083 filed Aug. 15, 2012, and claimspriority to and the benefit of U.S. Provisional Patent Application No.61/688,247 filed May 10, 2012, U.S. Provisional Patent Application No.61/704,863 filed Sep. 24, 2012, and U.S. Provisional Patent ApplicationNo. 61/803,678 filed Mar. 20, 2013, each of which is incorporated hereinby reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The subject disclosure is directed to surgical implants, and moreparticularly, to orthopedic bone plates for internally fixating anddynamically stabilizing fractured bones and to screws for use with suchbone plates.

2. Description of Related Art

Bone fractures often require stabilization by internal fixation. Boneplates are among the most common orthopedic implants used to stabilizeand internally fixate bone fractures. A typical bone plate is a rigidmetal plate with guide holes through which bone screws can be passed.Bone screws are usually threaded into the bone above and below thefracture to secure the bone plate, thereby rigidly stabilizing andfixating the fracture.

There has been increasing emphasis on bone plates that are capable ofproviding compression of the fracture as well as stabilization. Mostconventional compression plates however, are made of metal with amodulus of elasticity that is higher than that of bone and therefore,these compression plates have a limited ability to apply controlledamounts of compressive force to a fracture. Moreover, the use of suchbone plates produces a mechanical system in which the majority of thestress is borne by the plate rather than the bone. This can impair thehealing process in a fractured bone. Furthermore, it is now known that acontrolled compressive load should be maintained across a fracture topromote rapid healing. Conventional, static bone plates do not provideor maintain such conditions.

An example of a dynamic vertebral column plate is disclosed in U.S.Patent PG Publication No. 2010/0234895 to Hess published on Sep. 16,2010, the disclosure of which is herein incorporated by reference in itsentirety for purposes of enablement.

SUMMARY OF THE INVENTION

Clearly, there is a need in the art for a dynamic bone plate that can bereadily used to stabilize bone fractures.

In one embodiment, the subject technology is directed to a bone fractureplate assembly including a female plate portion and a male plateportion. The female plate portion has an upstanding post, a femaledovetail, two apertures for fasteners, and an arm extending from a firstend parallel to the female plate portion. The arm has a plurality ofratchet teeth grouped together. The male plate portion has twoupstanding posts, a male dovetail for coupling into the female dovetailso that the plate portions only move linearly with respect to eachother, a slot for receiving the arm, two apertures for fasteners, and apawl for engaging the ratchet teeth. A spring dynamically connects theplate portions by applying a compressive load therebetween. The springhas a head portion defining a hole for coupling to the post of thefemale plate portion as well as a pair of elongated ears extending fromthe head portion. Each ear defines a slot for coupling to the posts ofthe male plate portion, respectively. The male dovetail inserts in thefemale dovetail so that the arm extends into the slot of the male plateportion and the ratchet teeth are engaged by the pawl to retain theplate portions together, and the spring mounts on the posts of the plateportions such that the spring biases the male and female plate portionstogether.

The arm may also include a first tooth on a distal end, the first toothbeing linearly spaced from the plurality of ratchet teeth. The firsttooth interacts with a second pawl on the male plate portion forselectively locking the bone fracture plate assembly in an open positionin which the male and female plate portions are held apart. The arm isdeflectable so that the first tooth can be disengaged from the secondpawl to unlock the plate portions.

A top plate couples to the male and female plate portions for coveringthe spring. The top plate defines a hole for allowing a user to deflectthe arm to separate the first tooth from the second pawl so that thespring dynamically biases the male and female plate together. The springhas a generally V-shape. The hole of the spring and the post of thefemale plate portion are square-shaped to prevent rotation of the springwith respect to the female plate portion.

In another embodiment, the subject technology is directed to a boneplate assembly including at least first and second plate segmentsadapted and configured for movement relative to one another from aspaced apart position and an approximated position. Ratchet meansallowing the first and second plate segments to move from theapproximated position while preventing the first and second platesegments from moving toward a spaced apart position. The ratchet meansincludes a ratcheting pawl member operatively associated with the firstplate segment and a rack of ratchet teeth provided on the second platesegment for interacting with the pawl member.

In still another embodiment, the subject technology is directed to abone fracture plate assembly including a first plate portion, a secondplate portion coupled to the first plate portion so that the plates movewith respect to each other linearly, and a spring tensioning mechanismfor dynamically connecting the first and second plate portions such thatwhen mounted on opposite sides of a bone fracture, the first and secondplate portions apply a compressive load to the bone fracture.

Preferably, first means are provided for selectively limiting traveltogether between the first and second plate portions to create an openposition and second means are provided for selectively limitingseparation between the first and second plate portions to create aclosed position. The first means can be a distal ratchet tooth and afirst pawl associated with the first and second plate portions,respectively, and the second means can be a set of ratchet teeth and asecond pawl associated with the first and second plate portions,respectively. Adjustment means are associated with at least one of theplate portions for adjusting a force vector of the spring tensioningmeans relative to an angle of the bone fracture. In one embodiment, thespring tensioning mechanism is a spring mounted on posts and theadjustment means is a plurality of mounting locations for the spring.Also, adjustment means can be associated with at least one of the plateportions for applying a pre-load to the compression mechanism (e.g.,spool can be turned, plate can be selectively ratcheted by surgeon,etc.).

It should be appreciated that the present technology can be implementedand utilized in numerous ways, including without limitation as a kit, aprocess, an apparatus, a system, a device, a method for applications nowknown and later developed. These and other unique features of thetechnology disclosed herein will become more readily apparent from thefollowing description and the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

So that those having ordinary skill in the art to which the disclosedtechnology appertains will more readily understand how to make and usethe same, reference may be had to the following drawings.

FIG. 1 is a perspective view of a bone plate assembly in the static oropen position in accordance with the subject technology.

FIG. 2 is an exploded perspective view of the bone plate assembly ofFIG. 1.

FIG. 3 is a top view of the bone plate assembly of FIG. 1 with a portionof the top plate cutaway.

FIG. 4 is a partial sectional local view taken at line 4-4 of FIG. 3 toillustrate the locking of the bone fracture plate assembly in the staticor open position.

FIG. 5 is a perspective view of the bone plate assembly showing a toolurging the arm to transition from the open to the closed position.

FIG. 6 is a partial sectional local view taken at line 6-6 of FIG. 5 toillustrate transition to the dynamic or closed position.

FIG. 7 is a partial sectional local view taken at line 7-7 of FIG. 5 toillustrate the dynamic closed position.

FIG. 8 is a perspective view of a bone plate assembly being fastened toa bone in the static or open position in accordance with the subjecttechnology.

FIG. 9 is a perspective view of a bone plate assembly fastened to a bonein the dynamic or closed position in accordance with the subjecttechnology.

FIG. 10 is a top view of another bone plate assembly in the static oropen position in accordance with the subject technology.

FIG. 11 is a sectional view of the bone plate assembly of FIG. 10 in thestatic or open position.

FIG. 12 is a sectional view of the bone plate assembly of FIG. 10 in thedynamic or closed position.

FIG. 13 is a perspective view of still another bone plate assembly inthe static or open position in accordance with the subject technology.

FIG. 14 is a perspective view of the bone plate assembly of FIG. 13 inthe closed position.

FIG. 15 is a perspective view of yet another bone plate assembly in thestatic or open position in accordance with the subject technology.

FIG. 16 is a top view of an alternative spring mechanism with a lockingfeature in accordance with the subject technology.

FIG. 17 is a top view of another alternative spring mechanism with alocking feature in accordance with the subject technology.

FIG. 17 a is a detailed view of the alternative spring mechanism of FIG.17.

FIG. 18 is a plan view of a section of a plate assembly of the subjectinvention, illustrating a ratchet mechanism on the outer bars thatallows two plate segments to move toward one another to shorten thelength of the plate assembly, while preventing the two segments frommoving apart from one another.

FIG. 19 is an enlarged localized view of the ratchet mechanism shown inFIG. 18 when the plate segments are spaced apart from one another.

FIG. 20 is a localized view of the ratchet mechanism of FIG. 18 showingthe plate segments in an approximated position, in which the ratchet armprevents the plate segments from moving apart from one another.

FIG. 21 is a perspective view of a bone plate assembly fastened to abone in the dynamic or closed position in accordance with the subjecttechnology.

FIG. 21 a is a perspective view of another bone plate assembly fastenedto a bone in the dynamic or closed position in accordance with thesubject technology.

FIG. 22 is a perspective view of a bone plate assembly fastened to abone in the dynamic or closed position in accordance with the subjecttechnology.

FIG. 23 is a perspective view of a modular plate system fastened to abone in accordance with the subject technology.

FIG. 24 is an exploded view of another bone plate assembly in accordancewith the subject technology.

FIG. 25 is an exploded view of another bone plate assembly in accordancewith the subject technology.

FIG. 26 is an exploded view of another bone plate assembly in accordancewith the subject technology.

FIG. 26A is a cross-sectional view of the bone plate assembly of FIG.26.

FIG. 27 is a perspective view of a modular wedge for use with a boneplate assembly.

FIG. 28 is a perspective view of the modular wedge of FIG. 27 on a boneplate assembly in accordance with the subject technology.

FIG. 29 is a top view of another bone fracture plate assembly inaccordance with the subject technology.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The present disclosure overcomes many of the prior art problemsassociated with dynamic bone fracture plates. The advantages, and otherfeatures of the technology disclosed herein, will become more readilyapparent to those having ordinary skill in the art from the followingdetailed description of certain preferred embodiments taken inconjunction with the drawings which set forth representative embodimentsof the present invention and wherein like reference numerals identifysimilar structural elements.

All relative descriptions herein such as left, right, up, and down arewith reference to the Figures, and not meant in a limiting sense. Theillustrated embodiments can be understood as providing exemplaryfeatures of varying detail of certain embodiments, and therefore,features, components, modules, segments, mechanisms, elements, and/oraspects of the illustrations can be otherwise combined, interconnected,sequenced, separated, interchanged, positioned, and/or rearrangedwithout materially departing from the disclosed systems or methods.Additionally, the shapes and sizes of components are also exemplary andunless otherwise specified, can be altered without materially affectingor limiting the disclosed technology.

Referring to FIG. 1, a perspective view of a bone fracture plateassembly 100 in a static or open position in accordance with the subjecttechnology is shown. In brief overview, the bone fracture plate assembly100 provides not only stabilization but compression to facilitateadvantageous healing of the bone fracture. In some embodiments, thecompression force or vector is parallel to the length of the bonefracture plate assembly 100. The compression force may also be at anangle with respect to the length and even variable to match a particularapplication as described below with respect to different embodiments.

The bone fracture plate assembly 100 includes a female plate portion 102coupled to a male plate portion 120. The plate segments or plateportions 102, 120 are adapted and configured for movement relative toone another from a spaced apart or “open” position and an approximatedor “closed” position. Various means allow the plate portions 102, 120 tomove from open to closed while preventing the plate portions 102, 120from moving toward a spaced apart position. Further, the open positionis static, in which the bone fracture plate assembly 100 does not applycompression whereas the closed position is dynamic, in which the bonefracture plate assembly 100 applies compression.

Referring now to FIG. 2, an exploded perspective view of the bonefracture plate assembly of FIG. 1 is shown. The female plate portion 102has an upstanding post 104 located near a first end 106. The femaleplate portion 102 defines a female dovetail 108. A second end 110 of thefemale plate portion 102 defines two apertures 112 for fasteners (notshown) that attached the female plate portion 102 to bone.

An arm 114 extends from the first end 106 parallel to the female plateportion 102. The arm 114 has a plurality of ratchet teeth 116 grouped inan intermediate location. The arm 114 also includes a tooth 118 on adistal end 119, the tooth 118 being linearly spaced from the groupedteeth 116.

The male plate portion 120 has two upstanding posts 122. A first end 124of the male plate portion 120 defines a male dovetail 126 that couplesinto the female dovetail 108 so that the plate portions 102, 120 onlymove linearly with respect to each other when the dovetails 108, 126 areengaged. The dovetail shapes may be rounded, L-shaped, angular and otherconfigurations to allow substantially only linear movement when coupled.A second end 130 of the male plate portion 120 defines two apertures132, similar to the female plate portion 102, for bone fasteners (notshown). Each plate portion 102, 120 defines a tack hole 129.

The male plate portion 120 defines a slot 128 for receiving the arm 114,wherein the slot 128 terminates in an open area 131 that is lower thanthe adjacent area 127. In one embodiment, the open area 131 is about 0.6mm lower that the adjacent area 127. The male plate portion 120 has afirst pawl 134 for engaging the ratchet teeth 116 in the closed position(see FIG. 7) and a second pawl 135 for engaging the distal tooth 118 inthe open position (see FIG. 4). The pawls 134, 135 may extend into theslot 128 or the teeth 116, 118 may extend upward out of the slot 128, orboth to accomplish the interaction.

As best seen in FIG. 4, in the open position, only the distal tooth 118and second pawl 135 are engaged. This engagement prevents the bonefracture plate assembly 100 from moving to the closed position. In otherwords, the distal tooth 118 and second pawl 135 are configured to holdthe plate portions 102, 120 slightly separated, hence in the openposition. The amount of separation or gap 143 between the plates 102,120 is preferably about 2 mm. In other embodiments, the gap 143 is lessor more than 2 mm with a range of 2-5 mm being appropriate for mostapplications. As best seen in FIG. 6, in order to release the engagementof the distal tooth 118 and second pawl 135, the arm 114 is deflectableso that the distal tooth 118 can be disengaged from the second pawl 135.When released, the plate portions 102, 120 are pulled into the closedposition by a spring 140.

Referring to FIGS. 2 and 3 and 5, the spring 140 extends from the femaleplate portion post 104 to the male plate portions posts 122 todynamically connect the plate portions 102, 120 by applying acompressive load therebetween. The spring 140 has an apex or headportion 142 defining a hole 144 for coupling to the post 104.Preferably, the hole 144 of the spring 140 and the post 104 of thefemale plate portion 102 are square-shaped to prevent rotationalmovement of the spring 140. Triangular, star, rectangular, trapezoidal,hexagon, key-hole and many shapes as well as simply spot welding,clipping, pinning, and screwing the spring 140 to the female plateportion 102 would accomplish the same result of rotationally fixing thespring 140 with respect to the female plate portion 102. The post 104and hole 144 may also be round to allow for rotation.

A pair of elongated ears 146 extend from the head portion 142. Each ear146 defines a slot 148 for coupling to the posts 122 of the male plateportion 120, respectively. The posts 122 are shaped so that the posts122 can freely move within the slots 148. The generally V-shape of thespring 140 creates a compression force between the plates 102, 120 thatgenerally biases the plates 102, 120 together. As noted above, in theopen position, the engagement of the distal tooth 118 and second pawl135 prevents the spring's compression force from bringing the plates102, 120 together.

In a preferred embodiment, the spring 140 is fabricated from a memoryalloy such as nitinol so that the ears will press outward on the posts122 to create a force vector that pulls the plates 102, 120 together.The spring may take many different shapes as well such as a C-shape, aU-shape, a M-shape with two flex points, a V-shape as well as moretypical coil and flexure spring arrangements, whether it be one or aplurality of springs to create the desired force.

Referring to FIGS. 1-7, the bone fracture plate assembly 100 alsoincludes a top plate 150 coupled to the plate portions 102, 120 forcovering the spring 140. The top plate 150 is preferably welded to oneof the plate portions 102, 120. In another embodiment, the top plateincludes a lip that is captured in the dovetails 108, 126 whenassembled. The top plate may also include a depending projection (notshown) that engages the female plate portion 102 and the spring 140 tofix the head portion 142 to the female plate portion 102. The top plate150 defines a hole 152 for allowing the surgeon to deflect the arm 118as described below with respect to FIGS. 6, 7 and 9.

Referring now to FIG. 4, as noted above, when assembled, the maledovetail 126 inserts in the female dovetail 108 so that the arm 114extends into the slot 128 and the spring 140 is placed over the posts104, 122. Although the spring 140 urges the plate portions 102, 120together, the distal tooth 118 engages the second pawl 135 to maintainthe bone fracture plate assembly 100 open. The top cover 150 is in placeand the bone fracture plate assembly 100 is ready for deployment.

Referring now to FIG. 8, a perspective view of the bone fracture plateassembly 100 being fastened to a bone 50 with a fracture 52 is shown.Preferably, the fracture 52 has a gap 54 that will be closed by the bonefracture plate assembly 100. Initially, the bone fracture plate assembly100 is in the static or open position. The surgeon places the bonefracture plate assembly 100 on the bone 50 so that the length of thebone fracture plate assembly 100 is perpendicular to the bone fracture52. This aligns the compression force vector to be perpendicular to thebone fracture 52 as well.

To hold the bone fracture plate assembly 100 in place, the surgeon mayuse a temporary fastener (not shown) in the tack holes 129 totemporarily mount the bone fracture plate assembly 100. The tack holes129 are particularly useful when the bone fracture plate assembly 100 isnot preassembled and/or does not include a locking mechanism to maintainthe open condition. In such case, the surgeon partially assembles thebone fracture plate assembly in place, may tack it down and engage thespring mechanism. The tack holes 129 can also be used after screwinsertion with a tool to “pre-compress” the plate by pinching the platesegments together.

Still referring to FIG. 8, after tacking the bone fracture plateassembly 100 temporarily in place in the open position, the surgeonfixes the bone fracture plate assembly 100 more permanently by insertingbone fasteners 56 through the holes 112, 132 and into the bone 50 with ascrewdriver 58.

Referring to FIGS. 6 and 9, after fixing the bone fracture plateassembly 100 about the fracture, the surgeon uses a pointed tool 60 tomomentarily deflect the arm 114 so that the distal tooth 118 disengagesthe second pawl 135. At this point, the compression force of the spring140 pulls the plate portions 102, 120 together to close not only theplate gap 143 but the bone fracture 52/bone fracture gap 54 as well. Itis envisioned that the plate portions 102, 120 do not need to completelyclose.

Referring now to FIG. 7, a sectional local view taken at line 7-7 ofFIG. 5 illustrates the dynamic closed position. As the plate portions102, 120 come together into the closed position, the distal tooth 118moves away from the second pawl 135 so that when the arm 114 returns tothe normal position, the distal tooth 118 no longer engages the secondpawl 135. In another embodiment, the arm 118 bends permanently out ofthe way. For example, the arm 118 may have a crease, indentation orother predefined weak area upon which the arm 118 bends so that oncepushed out of the way, the distal tooth 118 and the second pawl 135 donot re-engage.

As the plate portions 102, 120 come together, the first pawl 134 and theplurality of teeth 116 become engaged to prevent the plate portions 102,120 from subsequently moving apart. Even though the bone fracture hasbeen closed by the bone fracture plate assembly 100, the spring 140continues to apply a compressive force across the fracture to aid in thehealing process.

Referring now to FIGS. 10-12, a top open, an open sectional and a closedsectional view, respectively, of another bone fracture plate assembly200 in accordance with the subject technology is shown. As will beappreciated by those of ordinary skill in the pertinent art, the bonefracture plate assembly 200 utilizes similar principles to the bonefracture plate assembly 100 described above. Accordingly, like referencenumerals preceded by the numeral “2” instead of the numeral “1”, areused to indicate like elements. The primary difference of the bonefracture plate assembly 200 in comparison to the bone fracture plateassembly 100 is the modification of the structure to maintain the bonefracture plate assembly 200 in the open position. Thus, the followingdescription mainly addresses this modification.

In the open position shown in FIG. 11, the male plate portion 220 stilldefines a slot 228 into which the arm 214 extends but a captive screw256 extends into the slot 228 to act as a stop against the distal end219 of the arm 214. Once the bone fracture plate assembly 200 is fixedin place about a fracture, the surgeon backs out the captive screw 256(or removes the screw 256 altogether depending upon how it isconfigured), to allow the plate segments 202, 220 to come together inthe dynamic or closed position.

Referring now to FIGS. 13 and 14, a perspective open and a perspectiveclosed view, respectively, of another bone fracture plate assembly 300in accordance with the subject technology is shown. As will beappreciated by those of ordinary skill in the pertinent art, the bonefracture plate assembly 300 utilizes similar principles to the bonefracture plate assemblies 100, 200 described above. Accordingly, likereference numerals preceded by the numeral “3” instead of the numeral“1” or “2”, are used to indicate like elements. The primary differenceof the bone fracture plate assembly 300 is again modification of thestructure to maintain the bone fracture plate assembly 300 in the openposition. Thus, the following description mainly addresses thismodification.

In the open position shown in FIG. 13, the male plate portion 320includes a selectively rotatable cam 360 that engages a block 362 on thedistal end 319 of the arm 314. The block 362 may define a cupped surface(not explicitly referenced), that helps capture the cam 360. The cam 360and block 362 are sized so that when engaged, the bone fracture plateassembly 300 remains open against the spring force. To transition to thedynamic closed position in FIG. 14, the surgeon simply rotates the cam360 off the block 362. The cam 360 can be rotated back to re-engage theblock 362 to spread the plate segments 302, 320 back to the openposition.

Referring now to FIG. 15, a perspective view of yet another bonefracture plate assembly 400 in the static or open position in accordancewith the subject technology is shown. Again, the bone fracture plateassembly 400 utilizes similar principles to the previously discussedbone fracture plate assemblies 100, 200, 300 so similar numbering isused. The bone fracture plate assembly 400 includes a central femaleplate segment 402 and two outer male plate segments 420.

To lock the bone fracture plate assembly 400 in the open position, cams460 are set against cupped blocks 462. To unlock the bone fracture plateassembly 400, the cams 460 are rotated away from the blocks 462. Ratherthan central dovetails, the bone fracture plate assembly 400 has atleast one bar 466 extending from the male plate segments 420 into agroove 468 formed in the female plate segement 402. In the preferredembodiment, each male plate segment 420 has an outer bar 466 on eachside of the spring 440 within a corresponding groove 468 in a slidingarrangement to act as a linear guide. Each bar 466 is coupled to thefemale plate segment 402 by a pin 470 extending into the female platesegment 402 through a slot 472 formed in the bar 466. Alternatively, thebars 466 and groove 468 may be a dovetail arrangement. The bone fractureplate assembly 400 also includes a fastener locking member 469 thatpartially extends into the mounting holes to engage a ridge in thefasteners (not shown) or completely cover the fasteners to retain thefasteners. Alternatively, the locking member 469 may seat on top of ashoulder on the fastener to retain the fastener.

It is noted that the bone fracture plate assembly 400 does not includeratchet means for allowing the plate segments 402, 420 to move closertogether while preventing the plate segments 402, 420 from moving towarda spaced apart position. Referring now to FIG. 16, a top view of analternative spring 540 with a locking feature 576 that can be utilizedwith all of subject technology is shown. The spring 540 is V-shaped withan apex hole 544 coupled to a post 504. The slots 548 similarly coupleto posts 522 however the slots 548 form a triangular locking feature 576such that upon the posts 522 moving down the slot 548, the lockingfeature 576 prevents the posts 522 from moving upward to, in effect,prevent the plates 502, 520 from separating once brought together. Theposts 522 may also have a triangular shape to more effectively interactwith the triangular locking feature 576. In another embodiment, theslots 548 are arcuate or kidney shaped so that once the posts 522 movefrom the outer end and overcome the intermediate hump, the posts 522come to rest in the inner end and are effectively retained there. Inanother embodiment, the locking feature 576 is simply semi-circularridges that the posts 522 can pass over but effectively rest in as aplurality of detent positions.

Referring now to FIG. 17 and FIG. 17 a, a top view of anotheralternative spring 640 with a locking feature 676 is shown. The lockingfeature 676 includes a ratcheting pawl member 678 on the female platesegment 602 and a rack 680 of ratchet teeth provided on the male platesegment 620 for interacting with the pawl member 678.

Referring now to FIG. 18, there is illustrated another dynamic boneplate assembly 700 that includes at least first and second platesegments 722 and 724, which are adapted and configured for movementrelative to one another from a spaced apart position shown in FIG. 19 toan approximated position shown in FIG. 20. A ratcheting pawl member 782is on the first plate segment 722 and a rack of ratchet teeth 784 areprovided on the outer bar 766 of the second plate segment 724 forinteracting with the pawl member 782. This ratchet mechanism allows thefirst and second plate segments 722, 724 to move from the spaced apartposition of FIG. 19 to the approximated position of FIG. 20, whilepreventing the first and second plate segments 722, 724 from moving backtoward a spaced apart position.

Referring now to FIG. 21, is a somewhat schematic perspective view of abone fracture plate assembly 800 fastened to a bone 50 in the dynamic orclosed position in accordance with the subject technology. The bonefracture plate assembly 800 provides an ability to vary the position ofthe compressive force vector with respect to the length of the bonefracture plate assembly 800. As a result, for an angled bone fracture52, the compressive force vector can be aligned to be substantiallyperpendicular to the angled bone fracture 52.

The bone fracture plate assembly 800 has two opposing plate segments802, 820 each plate segment 802 defining holes 804 for fasteners 806 formounting to the bone 50. A first central plate 808 is mounted on one ofthe plate segments 802 such as by a rivet (not shown). A second centralplate 810 is mounted on the other of the plate segments 802. The firstcentral plate 808 has preferably fixed two upstanding posts 814. Thesecond central plate 810 has one upstanding post 816 that movably mountswithin an arcuate slot 818. Thus, when the spring 840 is mounted on theposts 814, 816, the post 816 can be moved and locked within the arcuateslot 818 to rotate the compressive force vector to align substantiallyperpendicularly to the bone fracture 52. The spring 840 may be any ofthe versions disclosed herein, an elastic, a coiled wire and the like.

FIG. 21 a is a perspective view of another bone plate assembly 800 afastened to a bone 50 in the dynamic or closed position in accordancewith the subject technology. The bone plate assembly 800 a has outerplates 802 a that mount to the bone 50. Each outer plate 802 a has acentral plate 810 a that rotatably extends to cooperate with theopposing central plate 810 a via a spring 840 a. Linear guides 811 a areprovided on each side of the spring 840 a so that the force vector alignwith the length of the central plates 810 a. Once the bone plateassembly 800 a is in place, the pivot point 813 a of the central plates810 a can be locked down. For example, the pivot point 813 a may be apartially inserted screw, which is fully inserted to lock down thecentral plates 810 a.

FIG. 22 is a perspective view of another bone plate assembly 900fastened to a bone 50 in the dynamic or closed position in accordancewith the subject technology. The bone plate assembly 900 includes outerplates 902, which may or may not be linearly aligned lengthwise. Insteadof opposing central plates 810 a like in FIG. 21 a, the bone plateassembly 900 has a central disc 911 that can be selectively rotated. Thedisc 911 has two-sub parts 913 that are separated to allow linearmovement therebetween. A spring 940 spans the parts 913 to create acompressive force. Once the bone plate assembly 900 is in place, thepivot point 915 of the disc 911 can be locked down. As noted herein, thedisc 911 can be adapted to any of the bone plate assemblies of thesubject technology to provide adjustments of the compression forcevector to be about perpendicular to the bone fracture.

FIG. 23 is a modular plate system 1000 in perspective view. The modularplate system 1000 again allows aligning the compression force vector ofone or more bone fracture plate assemblies 1002 perpendicularly to oneor more bone fractures 52. The modular plate system 1000 includes aframe 1004 that couples to one or more bone fracture plate assemblies1002 by one or more bolts 1006.

In FIG. 23, one bone fracture plate assembly 1002 is shown and the ends1008 of the frame 1004 are coupled to the bone 50 by simple plates 1010and fasteners 1012. Alternatively, additional and intermediate bonefracture plate assemblies may couple to the frame 1004 so that the frame1004 provides structural support to the bone 50 or spine as the case maybe.

FIG. 24 is an exploded view of another bone plate assembly 1100 inaccordance with the subject technology. The male plate portion 1120 ofthe bone plate assembly 1100 has an engagement member 1181 with acentral flexible tab 1180 with ratchet teeth 1182 thereon. The maleplate portion 1120 also defines a distal cavity 1184 in the engagementmember 1181. The female plate portion 1102 defines a hollow 1186 (shownin phantom line), or a dovetail as the case may be, that snugly receivesthe engagement member 1181. A passage 1188 through the female plateportion 1102 allows a linear spring 1190 to extend through the femaleplate portion 1102 so that a head 1192 of the linear spring 1190 iscaptured in the cavity 1184. Another end of the spring 1194 is enlargedto be captured in a hollow 1196 of the female plate portion 1102. Thus,when assembled, the linear spring 1190 will urge the plate portions1102, 1120 together. The female plate portion 1102 forms a window 1198so that the ratchet teeth 1182 couple thereto for preventing the plateportions 1102, 1120 from separation unless the flexible tab 1180 ispushed downward.

FIG. 25 is an exploded view of still another bone plate assembly 1200 inaccordance with the subject technology. The bone plate assembly 1200 isquite similar to the bone plate assembly 1100 except that the flexibletab 1280, spring 1290, cavity 1284 and hollow 1188 are reconfigured.Hence, like reference numerals are used to indicate like elementswhenever possible as has been conventional throughout this description.

FIG. 26 is an exploded view of another bone plate assembly 1300 inaccordance with the subject technology and FIG. 26A is a cross-sectionalview of the bone plate assembly 1300. The bone plate assembly 1300 has amale plate portion 1320 and a female plate portion 1302, each of whichforms several dovetail fingers 1327, 1329 that, when interlocked, onlyallow linear travel of the plate portions 1302, 1320. The outer fingers1327 of the female plate portion 1302 and the outer fingers 1329 of themale plate portion 1320 include ratchet teeth 1382, 1383 that interactto deter the plates 1302, 1320 separating once engaged. Preferably, theouter fingers 1327 are sized and configured to deflect or flex tofacilitate smooth operation of the ratchet mechanism.

FIG. 27 is a perspective view of a modular wedge 60 for use with a boneplate assembly (shown in FIG. 28). The modular wedge 60 is dimensionedand configured to operatively engage an outer profile of at least one ofthe plate portions to act as a spacer. The modular wedge includes arectangular base 62 for supporting the bone plate assembly 1400. A firstend support 64 and a second end support 66 extend vertically fromopposing ends 67, 69 of the base 62. The first and second end supports64, 66 engage the outer profiles of at least one plate portion. Each ofthe first and second end supports 64, 66 includes a flange 64 a, 66 afor cupping and/or grasping the respective plate portion. The modularwedge 60 may be formed from a metal material, a biologic material,titanium, bone, PEEK, combinations thereof and the like.

Referring now to FIG. 28, a perspective view of the modular wedge 60 ona bone plate assembly 1400 is shown. The bone plate assembly 1400 isshown in the closed position as it would be with the modular wedge 60 inplace after final placement to provide separation and support betweenthe ends 1401, 1403 of the bone plate assembly 1400.

Referring now to FIG. 29, another bone plate assembly 1500 is shown. Thebone plate assembly 1500 includes wires 1590 extending between hubs 1592located on each plate portion 1502, 1520. The wires 1590 connect to oneof the plate segments 1502, 1520 and a spool 1594 which is free torotate. When the spool 1594 is rotated, the wires 1592 wrap around thespool 1594 thereby shortening the wire length and pulling the platesegments 1502, 1520 inward. Preferably, multiple wires 1590 are used.Also, the spool 1594 may be made with ratchet teeth to selectivelyrotate in one direction and, in turn, the wires 1590 could be tightenedbefore implantation, thereby creating a pre-load.

As can be seen upon review of the subject disclosure, selection of theconfiguration of the spring largely determines the compression force.Different cross-sections and angle combinations at the flex points ofthe spring result in different compression forces. Table 1 belowillustrates some exemplary data for various configuration springs of aU-shape as drawn in FIG. 15. The cross-section is taken at the flexpoints (reference numeral 481 as seen in FIG. 15) and the springs are0.5 mm thick. The angle would be the inner angle between the extendingears. Typically, the resulting force is about 9-10 lbs.

TABLE 1 CROSS-SECTION ANGLE F (lbs.) F (N) Spread (mm) 1.40 mm 95 8.638.184 2.08 1.40 mm 105 11.8 52.392 2.08 1.50 mm 95 11.8 52.392 2.181.30 mm 95 8.8 39.072 2.15 1.30 mm 105 11.8 52.392 2.18 1.35 mm 95 8.839.072 2.21

The springs were fabricated from nitinol. A preferred cross-section andangle combination will be approximately 1.36-1.40 mm and 97-100°,respectively. The springs are designed so that compression is maintainedeven when the plates have fully closed.

The bone plates and systems of the subject technology would beadvantageous to provide support and/or stabilization and/or compressionin a wide variety of applications. For example, without limitation, thesubject technology is useful in applications related to the clavicle,humerus, jaw bone, ulna, radius, hand (1-5 metacarpal), rib, scapula,parts of the lower body such as the femur, tibia, fibula, pelvis, andparts of the foot or ankle such as the calcaneus, metatarsal bones,talus and cuboid among many other possibilities. The subject technologyis particularly useful to stabilize the spine after, for example, aspinal procedure like disk removal.

While the subject invention has been shown and described with referenceto preferred embodiments of dynamic bone fracture plates, those skilledin the art will readily appreciate that various changes and/ormodifications may be made thereto without departing from the spirit andscope of the subject invention as defined by the appended claims. Forexample, each claim may depend from any or all claims, even in amultiple dependent manner, even though such has not been originallyclaimed.

1-23. (canceled)
 24. A bone plate assembly comprising: a female plateportion having: a post upstanding from the female plate portion; a firstend; a second end defining two apertures for fasteners; and an armextending from the first end parallel to the female plate portion, thearm defining a plurality of ratchet teeth; a male plate portion having:two posts upstanding from the male plate portion; a first end forcoupling to the first end of the female plate portion so that the plateportions only move linearly with respect to each other and a slot forreceiving the arm; a second end defining two apertures for fasteners;and a pawl for engaging the ratchet teeth; a spring for dynamicallyconnecting the plate portions by applying a compressive loadtherebetween, the spring having: an apex portion defining a hole forcoupling to the post of the female plate portion; and a pair ofelongated ears extending from the apex portion, each ear defining a slotfor coupling to the posts of the male plate portion, respectively; and amodular wedge member dimensioned and configured to operatively engage anouter profile of at least one of the plate portions, wherein the firstend of the male plate inserts in the first end of the female plate sothat the arm extends into the slot of the male plate portion and theratchet teeth are engaged by the pawl to retain the plate portionstogether, and the spring mounts on the posts of the plate portions suchthat the spring biases the male and female plate portions together. 25.The bone plate assembly as recited in claim 24, wherein the modularwedge member is formed from a material selected from the groupconsisting of a metal material, a biologic material, titanium, bone,PEEK and combinations thereof.
 26. The bone plate assembly as recited inclaim 24, wherein the modular wedge member engages the outer profile ofat least one of the plate portions when the plate portions are retainedtogether.
 27. The bone plate assembly as recited in claim 24, whereinthe modular wedge member includes a rectangular base for supporting thebone plate assembly.
 28. The bone plate assembly as recited in claim 27,wherein first and second end supports extend vertically from opposingends of the rectangular base.
 29. The bone plate assembly as recited inclaim 28, wherein each of the first and second supports has a flange forengaging the outer profile of at least one of the plate portions.
 30. Abone plate assembly for facilitating healing of a bone fracturecomprising: a first plate portion; a second plate portion coupled to thefirst plate portion so that the plates move with respect to each otherlinearly; a spring tensioning mechanism for dynamically connecting thefirst and second plate portions such that when mounted on opposite sidesof a bone fracture, the first and second plate portions apply acompressive load to the bone fracture; and a modular wedge memberdimensioned and configured to operatively engage an outer profile of atleast one of the plate portions.
 31. The bone plate assembly of claim30, wherein the spring mechanism includes: an apex defining a hole forcoupling to one of the plate segments; and a pair of elongated earsextend from the apex, each ear defining a slot for slidingly coupling toposts on the other plate portion, respectively, such that the elongatedears create a compression force between the plate portions thatgenerally biases the plate portions together.